Semiconductor optical devices and method for forming

ABSTRACT

A semiconductor optical device includes an insulating layer, a photoelectric region formed on the insulating layer, a first electrode having a first conductivity type formed on the insulating layer and contacting a first side of the photoelectric region, and a second electrode having a second conductivity type formed on the insulating layer and contacting a second side of the photoelectric region. The photoelectric region may include nanoclusters or porous silicon such that the device operates as a light emitting device. Alternatively, the photoelectric region may include an intrinsic semiconductor material such that the device operates as a light sensing device. The semiconductor optical device may be further characterized as a vertical optical device. In one embodiment, different types of optical devices, including light emitting and light sensing devices, may be integrated together. The optical devices may also be integrated with other types of semiconductor devices, such as vertical field-effect transistors.

FIELD OF THE INVENTION

This invention relates generally to semiconductor optical devices, andmore specifically, to vertically integrated semiconductor opticaldevices.

RELATED ART

Semiconductor optical devices may include light emitting diodes (LEDs),lasers, photo sensors, electroluminescent displays. One method knowntoday for forming such devices is through the use of Gallium Arsenide(GaAs) or Cadmium Selenide (CdSe). However, these materials are notcompatible with silicon CMOS processing, which prevents the ability toeffectively integrate them with other silicon-based devices.

Another known method used today, use semiconductor structures, such assilicon structure, which are planar where the contacts are on the topand bottom of the device. Thus, these type of planar structures occupylarge areas of silicon on a wafer. For example, FIG. 1 illustrates inschematic form, a cross section of a prior art optical device 8. Opticaldevice 8 includes a semiconductor p+ region 6, a semiconductor intrinsicregion 4, and a semiconductor n+ region 2, where typically, p+ region 6is located at a top surface of a semiconductor wafer and n+ region 2 islocated at a bottom surface of a wafer. Note that based on the materialschosen for semiconductor intrinsic region 4, device 8 may operate as anLED or a photo sensor. For example, in the case of an LED, intrinsicregion 4 may be formed of porous silicon or discrete siliconnanoclusters. However, although device 8 may be formed using silicon,the sidewalls of device 8 are not used for emitting or detecting lightor injecting holes and electrons. Therefore, device 8 does noteffectively use the available dimensions. Furthermore, if planarcontacts are needed, extra area is needed to route a contact to the n+region or p+ region to the opposite side of the wafer. Therefore, a needexists for improved semiconductor optical devices which may make use ofsidewall regions and which may be integrated with other types ofsemiconductor devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and is notlimited by the accompanying figures, in which like references indicatesimilar elements.

FIG. 1 illustrates a prior art optical device.

FIG. 2 illustrates a semiconductor device having an opening, inaccordance with one embodiment of the present invention.

FIG. 3 illustrates the semiconductor device of FIG. 2 after formation ofa layer of nanoclusters, in accordance with one embodiment of thepresent invention.

FIG. 4 illustrates the semiconductor device of FIG. 3 after formation ofmultiple layers of nanoclusters, in accordance with one embodiment ofthe present invention.

FIG. 5 illustrates the semiconductor device of FIG. 4 after formation ofan optional dielectric layer and a patterned masking layer, inaccordance with one embodiment of the present invention.

FIG. 6 illustrates the semiconductor device of FIG. 5 after formation offins, in accordance with one embodiment of the present invention.

FIG. 7 illustrates the semiconductor device of FIG. 6 after formation ofa patterned masking layer, in accordance with one embodiment of thepresent invention.

FIG. 8 illustrates the semiconductor device of FIG. 7 after formation ofa second semiconductor layer and after performing a first angledimplant, in accordance with one embodiment of the present invention.

FIG. 9 illustrates the semiconductor device of FIG. 8 after performing asecond angled implant, in accordance with one embodiment of the presentinvention.

FIG. 10 illustrates the semiconductor device of FIG. 9 after etching ofthe second semiconductor layer to form conductive electrodes, inaccordance with one embodiment of the present invention.

FIG. 11 illustrates the semiconductor device of FIG. 10 after forming aconductive layer, in accordance with one embodiment of the presentinvention.

FIG. 12 illustrates the semiconductor device of FIG. 11 after etchingportions of the conductive layer, in accordance with one embodiment ofthe present invention.

FIG. 13 illustrates a top-down view of the semiconductor device of FIG.12, in accordance with one embodiment of the present invention.

FIG. 14 illustrates the semiconductor device of FIG. 12 after forming aplanarization layer, in accordance with one embodiment of the presentinvention.

FIG. 15 illustrates the semiconductor device of FIG. 14 after etchingportions of the planarization layer and conductive layer, in accordancewith one embodiment of the present invention.

FIG. 16 illustrates the semiconductor device of FIG. 15 after removal ofthe planarization layer, in accordance with one embodiment of thepresent invention.

FIG. 17 illustrates the semiconductor device of FIG. 16 having threedifferent substantially completed elements, in accordance with oneembodiment of the present invention.

FIG. 18 illustrates a top-down view of a semiconductor device havingthree semiconductor elements, in accordance with an alternate embodimentof the present invention.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures maybe exaggerated relative to other elements to help improve theunderstanding of the embodiments of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

One embodiment of the present invention relates to an improved opticalsemiconductor device or element which may be integrated with other typesof optical semiconductor devices or elements or other types ofsemiconductor devices or elements. In one embodiment, nanoclusters areused within a photoelectric region of a vertical optical device, wherethe sides of the photoelectric region are in contact with conductiveelectrodes of different conductivity types which allow for the emittingof light. For example, these devices may include LEDs or lasers. Inanother embodiment, an intrinsic semiconductor material is used within aphotoelectric region of a vertical optical device, where the sides ofthe photoelectric region are in contact with conductive electrodes ofdifferent conductivity types which allow for the detecting of light. Forexample, these devices may include photo detectors or sensors. Also, asused herein, vertical optical devices are devices having conductiveelectrodes of different conductivity types formed along and in contactwith opposite sides of a photoelectric region, in which the conductiveelectrodes and photoelectric region overlie an insulating layer.

FIG. 2 illustrates a semiconductor device 10 having a semiconductorwafer 18 which has an opening 20 etched within a top layer, inaccordance with one embodiment of the present invention. In theillustrated embodiments, semiconductor wafer 18 is a semiconductor oninsulator (SOI) wafer having a substrate 12, a dielectric layer 14overlying substrate 12, and a semiconductor layer 16 overlyingdielectric layer 14. In the illustrated embodiment, opening 20 is formedusing conventional masking and etching techniques to expose underlyingdielectric layer 14. (Note that the shape of opening 20 may be adjustedas desired to create inclined sidewalls which may allow for varyinglight emitting characteristics of the resulting fin.) Substrate 12 maybe any type of material which provides mechanical support to overlyinglayers. For example, in one embodiment, substrate 12 may be anysemiconductor material such as silicon, gallium arsenide, silicongermanium etc., or any insulating material such as glass or sapphire.Dielectric layer 14 may be any type of insulating material, such as, forexample, oxide, nitride, glass, sapphire, etc. If dielectric layer 14 isof sufficient strength to provide mechanical support to overlyinglayers, substrate 12 may not be present. For example, dielectric layer14 may be formed of glass, and thus able to provide support foroverlying layers without the need for substrate 12.

FIG. 3 illustrates semiconductor device 10 of FIG. 2 after formation ofnanoclusters 22 overlying semiconductor layer 16 and within opening 20.Nanoclusters 22 are embedded within a dielectric layer (not numbered).In one embodiment, nanoclusters 22 are formed by thermal nucleation ofsilicon on an oxide surface. Alternatively, other materials such ascadmium selenide, zinc sulfide, and other photo active materials may beused for nanoclusters 22. The dielectric layer may be any type ofinsulating material, such as, for example, an oxide.

FIG. 4 illustrates semiconductor device 10 of FIG. 3 after the formationof multiple layers of nanoclusters, where each layer may be formed, forexample, by thermal nucleation of silicon on a subsequent oxide surface.Therefore, the dielectric layer between nanoclusters 22 may be formed ofoxide and controlled by the thermal oxidation. In one embodiment, thesize and density of nanoclusters 22 may be different in differentregions, and may be controlled by the thermal conditions during andafter formation of the nanoclusters. For example, different layers mayinclude different size and/or different densities of nanoclusters. Theformation of different size nanoclusters may allow for the generation ofdifferent light wavelengths. Also, each of nanoclusters 22 may vary insize and shape. For example, some nanoclusters may be round, whileothers may be oval or bone-shaped. In the illustrated embodiments,sufficient layers of nanoclusters are formed in order to fill opening20. In one embodiment, elements such as, for example, erbium may beincorporated into the nanoclusters to increase the light emittingefficiency.

In an alternate embodiment, a layer of porous silicon may be formedoverlying semiconductor layer 16 and filling opening 20. In thisembodiment, a deposited silicon layer may be etched to form poroussilicon. Alternatively, other porous semiconductor materials may beused, such as, for example, silicon germanium.

In yet another alternate embodiment, opening 20 may not be formed withinsemiconductor layer 16. In this alternate embodiment, nanocluscers 22and the surrounding dielectric layer may be formed overlyingsemiconductor layer 16. Also, sufficient layers of nanoclusters 22 maybe formed until a desired height is achieved to form the LED.

FIG. 5 illustrates semiconductor device 10 after planarization to removethe nanoclusters 22 and the surrounding dielectric layer overlyingsemiconductor layer 16. Therefore, only the portion of nanoclusters 22and the associated dielectric layer within opening 20 remain. Afterplanarization, a dielectric layer 24 is formed overlying semiconductorlayer 16 and nanoclusters 22. In one embodiment, dielectric layer 24 maybe a nitride or an oxide layer, or a combination thereof. Alternatively,dielectric layer 24 may not be present. A patterned masking layer 26 isformed over dielectric layer 24 to define fins for the formation ofvertical optical and semiconductor devices, in one embodiment, patternedmasking layer 26 is a photo resist layer where conventional masking andpatterning techniques may be used.

FIG. 6 illustrates semiconductor device 10 after formation of fins 28,30, and 32. Fin 28, having nanocluster portion 36 and overlyingdielectric portion 34, will be used in the formation of a light emittingelement (such as, for example, an LED or a laser). Fin 30, having anintrinsic semiconductor portion 40 and overlying dielectric portion 38,will be used in the formation of a light detecting element (such as, forexample, a photo sensor). Therefore, note that each of 36 and 40 may bereferred to as photoelectric regions. These photoelectric regions willoperate to emit or detect light or photons, as will be described below.Note that the photoelectric regions may or may not include overlyingdielectric portions such as portions 34 and 38. Fin 32, havingsemiconductor portion 44 (which may be subsequently doped) and overlyingdielectric portion 42, will be used in the formation of a verticalmetal-oxynitride field effect transistor (MOSFET). Note that each offins 28, 30, and 32 may not include a dielectric portion such asdielectric portion 34, 38, and 42.

FIG. 7 illustrates semiconductor device 10 of FIG. 6 after formation ofa patterned masking layer 46 which masks fins 28 and 30 while exposingfin 32. In one embodiment, patterned masking layer 46 is a nitride or anoxide layer. Conventional deposition and patterning techniques may beused to form patterned masking layer 46. After formation of patternedmasking layer 46, an implant may be performed into semiconductor portion44. For example, in one embodiment, boron is implanted for an n-type(i.e. NMOS) device and arsenic for a p-type (i.e. PMOS) device.Alternatively, semiconductor portion 44 may be left undoped. Afterdoping (if performed), dielectric regions 48 are formed along the sidesof semiconductor portion 44. In one embodiment, a thermal oxidation isused to form dielectric regions 48. Alternatively, a high dielectricconstant (K) material is deposited over and along the sides of fin 32.Therefore, note that in the illustrated embodiment fin 40 remains as anintrinsic semiconductor portion. After formation of dielectric regions48, patterned masking layer 46 may be removed, using, for example, aconventional wet or dry etch technique.

FIG. 8 illustrates semiconductor device 10 of FIG. 7 after formation ofa second semiconductor layer 50 overlying dielectric layer 14 and fins28, 30, and 32. Second semiconductor layer 50 may be any type ofsemiconductor material, such as, for example, silicon or silicongermanium. After formation of second semiconductor layer 50, an angledimplant 52 of a first species is performed into second semiconductorlayer 50 from a first direction. Angled implant 52 results in regions54, 56, and 58 doped with the first species. The first species has afirst conductivity type, which, in the illustrated embodiment of FIG. 8,is n+. Tn one embodiment, the n+ species may include, for example,phosphorous or arsenic. FIG. 9 illustrates semiconductor device 10 ofFIG. 7 after an angled implant 60 of a second species is performed intosecond semiconductor layer 50 from a second direction, different fromthe first direction. Angled implant 60 results in the formation ofregions 62, 64, and 66 doped with the second species. The second specieshas a second conductivity type, different from the conductivity type ofthe first species in FIG. 8, which, in the illustrated embodiment ofFIG. 9, is p+. In one embodiment, the p+ species may include, forexample, boron. Regions that respectively separate regions 54, 62,regions 56, 64 and regions 58,66 are regions which include both speciesdue to an overlap in angled implants 52 and 60. These regions will beelectrically highly resistive compared to those regions in which onlyone species is implanted. Note that angled implant 52 forms regions of afirst species within second semiconductor layer 50 along one side ofeach of fins 28, 30, and 32 while angled implant 60 forms regions of asecond species within second semiconductor layer 50 along an oppositeside of each of fins 38, 30, and 32. Note that in alternate embodiments,angled implants 52 and 60 may be performed in the reverse order. Alsonote that each of angled implants 52 and 60 can be performed using anyspecies, where the first species may be implanted before or after thesecond species.

In an alternate embodiment, a patterned masking layer (not shown) may beused to mask fin 32 and the portions of second semiconductor layer 50overlying fin 32 and portions of second semiconductor layer 50 along thesides of fin 32 during angled implants 52 and 60 such that regions 58and 66 are not formed.

FIG. 10 illustrates semiconductor device 10 of FIG. 9 after ananisotropic etch of second semiconductor layer 50 to form electrodes 72,74, 76, 78, 80, and 82 (which may also be referred to as conductiveelectrodes 72, 74, 76, 78, 80, and 82, respectively). This etch isolatesthe n+ and p+ regions and removes most or all of highly resistive suchas portions 68 and 70 of FIG. 9. Electrode 72 is formed along a firstside of fin 28 and has a first conductivity type, and electrode 74 isformed along a second side, opposite the first side, of fin 28 and has asecond conductivity type, different from the first conductivity type.Each of electrodes 72 and 74 are coupled to the photoelectric region offin 28, and each of electrodes 72 and 74 and fin 28 are formed ondielectric layer 14. In the illustrated embodiment, electrode 72 is n+and electrode 74 is p+. Electrode 76 is formed along a first side of fin30 and has a first conductivity type, and electrode 78 is formed along asecond side, opposite the first side, of fin 30 and has a secondconductivity type, different from the first conductivity type. Each ofelectrodes 76 and 78 are coupled to the photoelectric region of fin 30,and each of electrodes 76 and 78 and fin 30 are formed on dielectriclayer 14. In the illustrated embodiment, electrode 76 is n+ andelectrode 78 is p+. Electrode 80 is formed along a first side of fin 32and has a first conductivity type, and electrode 82 is formed along asecond side, opposite the first side, of fin 32 and has a secondconductivity type, different from the first conductivity type. Each ofelectrodes 80 and 82 are coupled to the semiconductive material of fin28 and each of electrodes 80 and 82 and fin 32 are formed on dielectriclayer 14. In the illustrated embodiment, electrode 80 is n+ andelectrode 82 is p+. Therefore, in one embodiment, electrodes 72, 74, 76,78, 80, and 82 may be formed using a self-aligned spacer etch since theymay be formed in a manner similar to sidewall spacers. Note that in analternate embodiment, this etch is optional and thus, may not beperformed.

FIG. 11 illustrates semiconductor device 10 after formation of aconductive layer 84 overlying dielectric layer 14, fins 28, 30, and 32,and electrodes 72, 74, 76, 78, 80, and 82. In one embodiment, conductivelayer 84 may be of any conductive material, such as, for example,polysilicon, tantalum silicon nitride, titanium nitride, silicongermanium, or any combination thereof.

FIG. 12 illustrates semiconductor device 10 after patterning and etchingof conductive layer 84 and electrodes 72, 74, 76, 78, 80, and 82 to forma conductive portion 86 overlying fin 28 and electrodes 72 and 74, aconductive portion 88 overlying fin 30 and electrodes 76 and 78, and aconductive portion 90 overlying fin 32 and electrodes 80 and 82. FIG. 13illustrates a top down view of semiconductor device 10 of FIG. 12. Notethat after the patterning and etching of conductive layer 84 andelectrodes 72, 74, 76, 78, 80, and 82, three separate devices (alsoreferred to as elements) are formed, corresponding to each of fins 28,30, and 32. Note that each of the fins can have any shape. For example,fin 32 may have a dumbbell shape to accommodate source and draincontacts. Conventional photolithographic techniques may be used topattern and etch conductive layer 84 and electrodes 72, 74, 76, 78, 80,and 82.

FIG. 14 illustrates semiconductor device 10 of FIG. 12 after formationof a planarization layer 92 over dielectric layer 14 and conductiveportions 86, 88, 90. In one embodiment, planarization layer 92 is formedby depositing a photoresist layer. FIG. 15 illustrates semiconductordevice 10 of FIG. 14 after planarization of planarization layer 92 to alevel which exposes top portions of conductive portions 86, 88, and 90.In the illustrated embodiment, planarization layer 92 is etched toexpose the top portions of conductive portions 86, 88, and 90, andafterwards, the top portions of conductive portions 86, 88, and 90 areremoved, thus resulting in conductive portions 94, 96, 98, 100, 102, and104, all isolated from each other. Conductive portions 94 and 96 arelocated on opposite sides of fin 28 and are isolated from each other,conductive portions 98 and 100 are located on opposite sides of fin 30and are isolated from each other, and conductive portions 102 and 104are located on opposite sides of fin 32 and are isolated from eachother. In an alternate embodiment, conductive portion 90 may not beetched to form conductive portions 102 and 104 such that the resultingdevice will not include isolated gates. Note that during the etching ofconductive portions 86, 88, and 90, portions of electrodes 72, 74, 76,78, 80, and 82 may also be removed. FIG. 16 illustrates semiconductordevice 10 of FIG. 15 after removal of planarization layer 92.Conventional etch and cleaning techniques may be used to removeplanarization layer 92.

Therefore, as illustrated in FIG. 17, three devices or elements 140,142, and 144 are formed. In the illustrated embodiment, elements 140 and142 are vertical optical devices and element 144 is a verticalfield-effect transistor. In the illustrated embodiment, element 140,formed from fin 28, is a light emitting element, such as, for example,an LED or a laser. In the illustrated embodiment, element 142, formedfrom fin 30, is a light detecting element, such as, for example, a photosensor. In the illustrated embodiment, element 144, formed from fin 32,is a MOSFET. Therefore, one embodiment of the present invention mayallow for the integration of different types of elements or devices,including both optical semiconductor elements or devices and other typesof semiconductor elements or devices. In alternate embodiments, only oneor two types of elements may be formed. For example, in one embodiment,an array of light emitting elements such as element 144 may be formedwithout including elements such as elements 142 and 144. Note that inthe illustrated embodiment, the dielectric portions overlying thephotoelectric regions of fins 28 and 30 are removed, but in alternateembodiments, they may not be removed.

Element 140 may be used to emit light 146, where light refers to photonsthat are emitted in a wide range of wavelengths. For example, light mayinclude infrared, visible, and ultraviolet light. In element 140, the n+region operates as an electron source region and the p+ region operatesas a hole source region. Thus, the recombination of electron and holesin the nanoclusters (or, in an alternate embodiment, in the poroussemiconductor material, if used in place of the nanoclusters) emitsphotons. For example, in one embodiment, a voltage applied to electrodes72 and 74 causes the recombination of electron and holes in thephotoelectric region of element 140, thus causing the photoelectricregion to emit photons. In one embodiment, the sides of fin 28 may bevaried (such as, for example, by creating sidewalls that make cavitieswhich enable a laser or by angling the sides of opening 20 in FIG. 2) toresult in coherent light waves, i.e. a laser. Although element 140 isillustrated as emitting light from a top portion of fin 28, element 140may emit light in any direction along the sides of fin 28 and in a planevertical to the plane in which the figure is drawn. Therefore, element140 includes a photoelectric region in contact with electrodes 72 and 74of different conductivity types which allows element 140 to emit light.

Element 142 may be used to sense or detect light. In element 142, light148 is incident on the p-i-n junction formed by electrode 78, fin 30(having an intrinsic semiconductor photoelectric region), and electrode80. When light 148 is incident upon the p-i-n junction, a potentialdifference can be sensed between electrodes 76 and 78. (For example,when sensing light, a conductivity of the photoelectric region changesin response to changes in light intensity.) Therefore, element 142includes a photoelectric region in contact with electrodes 72 and 74 ofdifferent conductivity types which allows element 142 to detect or senselight.

FIG. 18 illustrates a top down view 106 of an alternate embodiment inwhich all elements are integrated such that each of the fins of theelements are linearly coupled. For example, as illustrated in FIG. 18, afin 108 may be used to form different types of elements, such aselements 140, 142, and 144 of FIG. 17. In this embodiment, a firstportion 110 of fin 108 may be formed having nanoclusters, in a mannersimilar to the formation of nanocluster portion 36 of FIG. 6, where thisfirst portion corresponds to an element 146. Alternatively, firstportion 110 may be formed of a porous semiconductor material. A secondportion 112 of fin 108 may be formed of intrinsic semiconductor materialwhere this second portion corresponds to an element 148, and a thirdportion 114 of fin 108 may be formed of doped or undoped semiconductormaterial where this third portion corresponds to an element 150. In theillustrated embodiment, each of first portion 110, second portion 112,and third portion 114 are all linearly coupled.

Each of the first, second, and third portions of fin 108 may thereforecorrespond to different types of elements or devices. For example,element 146 may be a light emitting element having electrodes 118 and120 and isolated conductive portions 116 and 122. Note that electrodes118 and 120 and isolated conductive portions 116 and 122 are similar toelectrodes 74 and 72 and isolated conductive portions 96 and 94,respectively. Therefore, element 146 operates similar to element 140.Element 148 may be a light detecting element having electrodes 126 and128 and isolated conductive portions 124 and 130. Note that electrodes126 and 128 and isolated conductive portions 124 and 130 are similar toelectrodes 78 and 76 and isolated conductive portions 100 and 98,respectively. Therefore, element 148 operates similar to element 142.Element 150 may be a MOSFET having source/drain regions 136 and 138, anda gate region 132. Note that element 150 includes an oxide 134 alongsides of third portion 114 of fin 108 underlying gate region 132. Notethat in this embodiment, gate region 132 is not separated into twoisolated portions. This can be done using conventional maskingtechniques such as using a nitride or oxide hard mask.

By now it should be appreciated that there has been provided improvedoptical semiconductor devices or elements for emitting and detectinglight. Also provided is a method for integrating these types of deviceswith each other and with other types of semiconductor devices such asMOSFETs or vertical MOSFETs. The integration of these types of devicesmay allow for a wide range of applications, such as, for example,opto-couplers, displays, cameras, and the electronic circuitry tocontrol them. The optical devices described herein may also be used toform photocells. Also note that each of the types of devices or elementsmay be independently used, as desired. Note that use of vertical opticaldevices (such as those illustrated in FIG. 17) may allow for reducedsurface area as compared to prior art planar devices which are laterallyformed within a semiconductor layer. Also, the sides of thephotoelectric region of a vertical optical device may allow for theability to use more of the photo emitting or detecting dimensions ascompared to prior art devices.

In the foregoing specification, the invention has been described withreference to specific embodiments. However, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the present invention as set forthin the claims below. Accordingly, the specification and figures are tobe regarded in an illustrative rather than a restrictive sense, and allsuch modifications are intended to be included within the scope of thepresent invention.

Although the invention has been described with respect to specificconductivity types or polarity of potentials, skilled artisansappreciated that conductivity types and polarities of potentials may bereversed.

Moreover, the terms “front”, “back”, “top”, “bottom”, “over”, “under”and the like in the description and in the claims, if any, are used fordescriptive purposes and not necessarily for describing permanentrelative positions. It is understood that the terms so used areinterchangeable under appropriate circumstances such that theembodiments of the invention described herein are, for example, capableof operation in other orientations than those illustrated or otherwisedescribed herein.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any element(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature or element of any or all the claims. As used herein, the terms“comprises,” “comprising,” or any other variation thereof, are intendedto cover a non-exclusive inclusion, such that a process, method,article, or apparatus that comprises a list of elements does not includeonly those elements but may include other elements not expressly listedor inherent to such process, method, article, or apparatus. The terms“a” or “an”, as used herein, are defined as one or more than one.

1. A method for forming a semiconductor optical device comprising:providing an insulating layer having a surface; forming a light emittingfin region on the surface of the insulating layer that has a height thatis greater than a width thereof; forming a conformal semiconductor layeroverlying and adjacent the light emitting fin region; doping theconformal semiconductor layer using two angled implants of oppositeconductivity type and respectively angled to opposite sides of the lightemitting fin region; partially removing the conformal semiconductorlayer adjacent the light emitting fin region and removing the conformalsemiconductor layer above the light emitting fin region, the partiallyremoving leaving a remainder thereof which is used to form a first lightemitting fin sidewall electrode having a first conductivity type on theinsulating layer and contacting a first side of the light emitting finregion, and form a second light emitting fin sidewall electrode having asecond conductivity type on the insulating layer and contacting a secondside of the light emitting fin region, the second side opposite thefirst side.
 2. The method of claim 1, wherein the light emitting finregion emits photons when a voltage is applied to the first and secondlight emitting fin sidewall electrodes.
 3. The method of claim 1,wherein the light emitting fin region comprises a plurality ofnanoclusters embedded in an insulating material.
 4. The method of claim1, wherein providing the insulating layer comprises forming theinsulating layer on a semiconductor substrate.
 5. The method of claim 1,wherein forming the light emitting fin region comprises forming thelight emitting fin region from at least one of cadmium selenide or zincsulfide.
 6. The method of claim 1, wherein the first conductivity typeis n+ and the second conductivity type is p+.
 7. The method of claim 1,wherein forming the first light emitting fin sidewall electrodecomprises using a first angled implant, from a first direction, toprovide the first conductivity type, forming the second light emittingfin sidewall electrode using a second angled implant from a seconddirection, to provide the second conductivity type, said light emittingfin region having a height sufficient to block doping of each lightemitting fin sidewall electrode from either the first direction or thesecond direction.
 8. The method of claim 7, further comprising formingand patterning a first conductive contact adjacent to and in directcontact with the first light emitting fin sidewall electrode, andforming and patterning a second conductive contact adjacent to and indirect contact with the second light emitting fin sidewall electrode. 9.The method of claim 1, wherein forming the first light emitting finsidewall electrode and the second light emitting fin sidewall electrodeare formed using a self-aligned spacer etch.
 10. The method of claim 1,wherein forming the light emitting fin region comprises embedding aplurality of nanoclusters in an oxide, wherein a density of theplurality of nanoclusters, and a size of each of the plurality ofnanoclusters varies throughout the oxide.
 11. A method comprising:providing a supporting layer; forming a first semiconductor layeroverlying the supporting layer; etching an opening in the firstsemiconductor layer where a light emitting device is desired; forming alayer of light emitting material overlying the first semiconductor layerand the opening; forming a dielectric layer overlying the layer of lightemitting material; providing a patterned masking layer overlying theopening and removing exposed material to form a fin structure comprisinglight emitting material on the supporting layer, the fin structure beingtaller than its width; forming a second semiconductor layer overlyingand adjacent the fin structure; angle implanting the secondsemiconductor layer from two opposing angles with opposite conductivityimplants; and removing the second semiconductor layer from above the finstructure to form a first electrode from the second semiconductor layer,the first electrode being on a first sidewall of the fin structure, saidremoving also forming a second electrode from the second semiconductorlayer, the second electrode being of opposite conductivity type from thefirst electrode and being on a second sidewall of the fin structureopposite from the first sidewall.
 12. The method of claim 11 comprising:biasing the first electrode and the second electrode to emit light fromthe light emitting material at a top of the fin structure.
 13. A methodcomprising: providing a base layer; forming a first semiconductor layeroverlying the base layer; etching an opening in the first semiconductorlayer where a light emitting device is desired; forming a layer of lightemitting nanoclusters overlying the first semiconductor layer and theopening; forming a dielectric layer overlying the layer of lightemitting nanoclusters; providing a patterned masking layer overlying theopening and removing exposed portions of the dielectric layer and thelayer of light emitting nanoclusters to form a fin structure comprisinglight emitting nanoclusters on the base layer, the fin structure beingtaller than its width; forming a second semiconductor layer overlyingand adjacent the fin structure; angle implanting the secondsemiconductor layer from two opposing angles with opposite conductivityimplants; and removing the second semiconductor layer from above the finstructure to form a first electrode from the second semiconductor layer,the first electrode being on a first sidewall of the fin structure, saidremoving also forming a second electrode from the second semiconductorlayer, the second electrode being of opposite conductivity type from thefirst electrode and being on a second sidewall of the fin structureopposite from the first sidewall.